JUCE SDK integration.

Makefile

@@ -646,3 +646,22 @@ test-steinberg-sdk: steinberg-sdk $(BUILD_DIR)/test_steinberg_sdk $(BUILD_DIR)/s
 	./$(BUILD_DIR)/test_steinberg_sdk "$(abspath $(STEINBERG_BUILD_DIR))/VST3/Release/xtc-sdk-examples.vst3"
 
 -include $(BUILD_DIR)/tests/unit/test_plugin_module_path.d $(BUILD_DIR)/tests/integration/test_steinberg_sdk.d $(BUILD_DIR)/examples/steinberg/render.d
+
+# Optional JUCE bridge/examples; externally supplied SDK, no downloads or installs.
+JUCE_ROOT ?=
+JUCE_BUILD_DIR ?= $(BUILD_DIR)/juce
+.PHONY: juce-examples test-juce
+juce-examples:
+	@test -n "$(JUCE_ROOT)" || { echo "Set JUCE_ROOT to an external JUCE 9 checkout (AGPLv3/commercial)."; exit 1; }
+	cmake -S examples/juce -B "$(JUCE_BUILD_DIR)" -DXTC_JUCE_ROOT="$(abspath $(JUCE_ROOT))" -DCMAKE_BUILD_TYPE=Release
+	cmake --build "$(JUCE_BUILD_DIR)" --target xtc-juce-render XtcJuceSynth_VST3 XtcJuceSynth_Standalone --parallel 3
+
+$(BUILD_DIR)/test_juce_plugin: $(BUILD_DIR)/tests/integration/test_juce_plugin.o $(BUILD_DIR)/libxtc.a
+	$(CC) $(LDFLAGS) -o $@ $^ -lm -ldl
+
+test-juce: juce-examples $(BUILD_DIR)/test_juce_plugin
+	xvfb-run -a $(PYTHON) tests/integration/test_juce_examples.py "$(JUCE_BUILD_DIR)/xtc-juce-render_artefacts/Release/xtc-juce-render"
+	xvfb-run -a ctest --test-dir "$(JUCE_BUILD_DIR)" --output-on-failure
+	xvfb-run -a ./$(BUILD_DIR)/test_juce_plugin "$(abspath $(JUCE_BUILD_DIR))/XtcJuceSynth_artefacts/Release/VST3/xtc JUCE Synth.vst3"
+
+-include $(BUILD_DIR)/tests/integration/test_juce_plugin.d